This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A paucity of information regarding the essential capacities underlying speech development precludes a complete model of communicative development for both normal and disordered speech. A primary objective of this research is to identify those physiologic proficiencies underlying the typical development of motor control for speech and to compare these data with atypical speech development. This information may detect early symptoms and describe atypical coordination noted for a given developmental speech disorder. The primary goal of this project is to quantify the adult model of motor control (coordination) for producing bilabial speech sounds, and comparing these measures with those obtained from very young children for the purpose of understanding basic tenets of speech motor development. This investigation is obtaining measures from English and Mexican Spanish speakers for the purpose of investigating how speech motor control is influenced by developing physiology and language. This investigation will use these cross-linguistic data to understand how linguistic constraints influence motor commands and how motor constraints delimit linguistic goals. The development of this normal model of coordination during specific productions of speech will be used for future investigations of disordered speech productions.